Our last few posts have focused on range hoods. We will wrap up this series with a few last thoughts on guidelines for a range hood's width, depth, and mounting height.

• Width of a Range Hood -- You always want to choose a range hood that is as wide, or wider than the your stove or cooktop. Following this guideline creates a capture area under the hood large enough to trap heat, steam, and smells given off by cooking. For example, a 36" cooktop should have a range hood 36" to 42" wide.

• Depth of a Range Hood -- To keep from hitting your head, a range hood's depth needs to be less than your cooking surface. The optimal depth will result in the range covering the rear burners and part of the front burners. 

• Mounting Height -- This is referring the distance between the bottom of the range hood and the top of the cooking surface. Ideally, this should 24" to 36". Like the width of a range hood, this will help capture the steam, heat, grease and smells generated by cooking. If the range hood is located more than 36" above the cooking surface, it will render the hood ineffective.

If you want to talk more about range hoods or are preparing for a kitchen update, please give us a call or stop by our showroom.  One of our designers would be happy to talk with you.   

When selecting a range hood, it is important to choose the correct size. CFM ... or cubic feet of air moved per minute ... is used to measure the size of a range hood. Selecting a range hood / blower's capacity needs to consider stove type, kitchen size, and ductwork.  Let's look at how to determine CFM requirements

Electric Stove / Range - One simple calculation requires 100 CFM for every linear foot of stove width. For example, with a 30" wide electric stove, your hood should be rated at 250 CFM or higher.  This is calculated by taking the stove width (30" equals 2.5 linear feet) times 100 CFM per linear foot.

Gas Cooktop - Compared to an electric stove, gas cooktops give off substantially more heat. Consequently, a larger hood is required. The first step in determining the necessary CFM is totaling the BTU's for all the burners. Typically, each gas burner will be between 5,000 to 15,000 BTU's. The output for a four burner gas cooktop will normally be around 40,000 BTU's. Divide the cooktop's total BTU's by 100 for the CFM requirement.  For a standard gas cooktop, a 400 CFM hood / blower (40,000 ÷ 100) would be needed. 

Kitchen Size -- You also need to consider the size of your kitchen. The larger the room, the larger the range hood. Industry guidelines call for turning over the air in a kitchen 15 times per hour. This is once every four minutes. To determine CFM, take the volume of the room (width x length x height), multiply by 15 exchanges per hour, and then divide by 60 minutes per hour. For a 12' x 16' room with 9' ceilings, the necessary CFM is 432 (12 x 16 x 9 x 15 ÷ 60 = 432). 

Ductwork - As air flows through ductwork and around corners, its progress is hindered. This needs to be considered in sizing the range hood blower. Guidelines call for adding 1 CFM for every foot of ductwork and 25 CFM for each turn. If the hood is vented through a roof cap, an additional 40 CFM needs to added.

After calculating CFM using these different methodologies, size your range hood based on the largest CFM requirement and then add for ductwork. This will result in the correct size for your home's range hood.

If you have more questions about remodeling or range hoods, please stop in our Carmel, Indiana showroom and talk with one of our designers. They will be happy to help.  

Our last post focused on the benefits of range hoods ... removing airborne contaminants, steam, and heat from your home. The next question is determining the style of range hood to select for your home. We will discuss focus on the three common range hood designs in this blog ... wall mount/chimney style, microwave/undercabinet, and ceiling mounted.

Wall / Chimney mounted hoods go directly against a kitchen wall, above the range or cooktop. This style typically prevents cabinets from being installed above the hood. Space also needs to be provided between the range hood and the cabinets flanking each side of the hood. Numerous shapes, styles, and materials are available to choose from.

Under Cabinet / Microwave hoods, like the wall / chimney option, attach directly to a kitchen wall. These units typically have smaller blower motors, so are not as powerful as a full-size range hood. From a price perspective, these are inexpensive. While performance may not be ideal, they can be a good answer depending on your kitchen's size and layout.

Finally, range hoods can be mounted to the ceiliing. These are "free-standing" and used over a cooktop / stove located in an island or peninsula. Installation of a ceiling mounted hood is more complex and best done by a contractor. This style is large enough to accomodate a powerful blower.

Range hoods are vented one of two ways ... outside of your home or recirculated back into the kitchen. Ideally, a range hood will be vented outside the home.  This gives optimal performance with regards to noise and air quality. However, venting outside the home is not always possible, requiring the air to be recirculated. One example requiring recirculation is a high-rise condominium. In a recirculating hood, charcoal filters are used to eliminate odors and airborne contaminants before sending the air back into the room. The downside of recirculation is a reduction in airflow, additional noise, and periodic cleaning. 

Watch for our next blog ... we will talk about CFM and sizing. Thinking about a kitchen remodel?  Give us a call or stop in our Carmel, Indiana showroom and let us help you.